The present invention relates to a process of preparation of a new memory thermoplastic composition from polycaprolactone and polyurethane. It relates also as new industrial product, to the thermoplastic composition obtained by this process. It relates also to the use of this new industrial product particularly in orthopedics as immobilising means.
It is known that the material most used to immobilise a part of the human body, and particularly a broken limb, is plaster. It is found that, in the field of orthopedic structure, bandages with plaster constitute immobilising means having a large number of drawbacks. In fact, plaster is heavy and little permeable to air, it absorbs and disperses X-rays, which hinders diagnosis by radiography, and it often gives rise to irritation of the skin.
It is also known that, to replace the plaster, it has been proposed in the past to use orthopedic structures of polycaprolactone. Polycaprolactone is a substance which has at room temperature high bending strength and high modulus elasticity, but which has the drawback from 50.degree. C. of becoming soft and very sticky. If polycaprolactone sheet is heated to a temperature above about 50.degree. C., it rapidly loses its mechanical strength and its elasticity, and it cannot even support its own weight.